The Internet has enabled information providers to easily provide multimedia information to users across the world. The amount of available information has increased exponentially in the time that the Internet has been accessible to the public.
As more and more users accessed large multimedia files from information providers, such as music and movies, the information providers' servers became overloaded. The bottleneck became the bandwidth that the servers could handle. Content Delivery Network (CDN) providers began placing caching servers across the Internet at geographic locations that served content to users in specific geographic regions. The caching servers contained mirror images of the information providers' multimedia files. This eased the burden on the information providers' servers by offloading the user requests to the caching servers. Replicating the information providers' multimedia files across the caching servers required a large amount of storage for infrequently accessed multimedia files. The number of files that are accessed within an information provider's collection of multimedia files is low in comparison to the total number of files in the collection.
CDN providers changed the role of the caching servers by only caching content that was recently accessed on the caching servers. When a cache miss occurred (where a requested multimedia file was not cached in the caching server's memory), the caching server would request the multimedia file from a content provider's server. This causes a delay in the response time for the caching server.
The approaches described in this section are approaches that could be pursued, but not necessarily approaches that have been previously conceived or pursued. Therefore, unless otherwise indicated, it should not be assumed that any of the approaches described in this section qualify as prior art merely by virtue of their inclusion in this section. Similarly, issues identified with respect to one or more approaches should not assume to have been recognized in any prior art on the basis of this section, unless otherwise indicated.